Ban said during a forum for democracy and development in Qatar’s capital Doha that an immediate cessation of hostilities plus talks on political transition are needed in Syria.
The UN chief warned that persistent fighting could hamper efforts for a political settlement.
"I call on all regional and international actors to use their influence on the parties, and to persuade them to negotiate in good faith on transitional arrangements," he said.
"Is there anything more urgent than resolving that nightmare?" he added.
The remarks came days after a meeting of world powers on Syria in Vienna failed to make a clear breakthrough.
At the end of the meeting co-chaired by the US and Russia, the International Syria Support Group pledged to bolster Syria’s fragile ceasefire and send humanitarian relief.
UN special envoy for Syria Staffan de Mistura said after the meeting that he wants to see signs of progress before setting a date for the resumption of negotiations.
On Saturday, the Russian Coordination Center, based in Hmeimim airbase, said that terrorist organizations breached the ceasefire agreement nine times over the past 24 hours, bringing the total number of breaches to 577 since truce took effect on February 27.
Syria has been gripped by foreign-backed militancy since March 2011. Damascus says Saudi Arabia, Turkey and Qatar are the main supporters of the militants fighting the government forces.
De Mistura estimates has estimated that over 400,000 people have been killed in the Syrian crisis, Press TV reported.
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